[카페,도와줘요!] 원서 한페이지 해석좀 부탁합니다 내공 100 겁니다

The discovery of electricity came piecemeal, having its origins with the discovery, around 400 BC or earlier, of the torpedo fish: a fish capable of generating an electric shock current of 100-150V to stun tis prey. It was used to treat a variety of ills and enjoyed limited but significant popularity for over 2000 yaears. Around 1750, batteries were invented. these provided a means of producing steady, direct current and were used by Galvani to demonstrate the effects of elec- tric current on frog nerve and muscle. Some medical practitioners and other enthusiasts were quick to adopt the therapeutic use of electri- cal stimulation using batteries, then known as 'Voltaic cells'. Torpedo fish lost their popularity due to their higher maintenance cost and lesser general availability.  A problem with batteries and torpedo fish is that they produce painful jolts rather than a smooth, sustained physiological response. A turning point came in the 1800s, when the then newly discovered induction coil was used to generate current pulses by devices known as Faradic stimulators, which were widely adopted by medical prac- titioners for patient treatment (Geddes, 1984). Faradic stimulators produce current pulses of brief duration, suitable for stimulating nerve, using electrodes in contact with the skin surface.  Around 1900 the alternator was invented: a device for producing sinusoidal alternating current (AC), which is still used, for example, to generate mains-supplied electricity. A French scientist, d'Arsonval pioneered the study of the physiological responses to AC electrical stimulation using the newly invented alternator and established that kHz frequency AC was best for producing comfortable, strong muscle contractions (d'Arsonval, 1984). In the 1950s Nemec (1959) pro- moted 'Interferential Therapy',a form of electrical stimulation,which is still popular, and which uses AC at afrequency around 4kHz, produced electronically, for stimulation of nerve and muscle. In the mid-1970s, a Russian scientist, Kots, pioneered the use of 2.5kHz AC for muscle strengthening and related uses and this led to the popularity of 'Russian' currents in clinical practice (Ward and shkuratova, 2002).  Early (pre-1980s) electromedical equipment was purpose designed and easily identified. Thus a clinician might use an 'interferential', 급해서 그러니 해석좀 부탁드리겠습니다 ㅠㅠ